• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.58-66
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• 2009

The telemetry of eight adult manchurian trouts (Brachymystax lenok tsinlingensis) in the upper part of the Nakdong River, which is the southern limit of distribution of manchurian trout on the Korean peninsula, was used to examine migration patterns and evaluate characteristics of over-wintering and the spawning season between December, 2007 and May, 2008. Based on the tracking data, the tagged fish showed a limited migration between adjacent pools, moving only up to $8.6m\;day^{-1}$ during the winter season (December to February). Hydraulic conditions of over-wintering pool areas were, ca. 1m depth, slow moving surface water with areas of sand and gravel. The migration of tagged individuals was successful, moving up to $96.2m\;day^{-1}$ during the spawning season. Two tagged individuals (BL4, BL6) exhibited upstream migration, whereas others showed downstream movements. The timing of upstream migration of the two individuals was consistent with an increasing phases of water level and discharge. The fishes migrating toward the down stream moved to the wide pool areas downstream, where they spent the summer season for the growth.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.7
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• pp.2751-2756
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• 2015

Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can specifically induce apoptosis limited to various cancer cells, so this reagent is considered a promising medicine for cancer therapy. TRAIL also exerts effects on non-apoptotic signals, relevant to processes such as metastasis, autophagy and proliferation in cancer cells. However, the mechanisms of TRAIL-regulated non-apoptotic signals are unclear. The purpose of this study was to investigate MADD/CXCR7 effects in TRAIL-mediated breast cancer cell migration. Materials and Methods: The ability of MADD/CXCR7 to regulate MVP signaling in TRAIL-mediated breast cancer cells migration was evaluated by transwell migration assay, quantitative RT-PCR, Western blotting and knock down experiments. Results: In this study, we found that treatment with TRAIL resulted in induced expression levels of MADD and CXCR7 in breast cancer cells. Knock down of MADD followed by treatment with TRAIL resulted in increased cell migration compared to either treatment alone. Similarly, through overexpression and knockdown experiments, we demonstrated that CXCR7 also positively regulated TRAIL-inhibited migration. Surprisingly, knock down of MADD lead to inhibition of TRAIL-induced CXCR7 mRNA and protein expression and overexpression of CXCR7 lead to the reduction of MADD expression, indicating that MADD is an upstream regulatory factor of TRAIL-triggered CXCR7 production and a negative feedback mechanism between MADD and CXCR7. Furthermore, we showed that CXCR7 is involved in MADD-inhibited migration in breast cancer cells. Conclusions: Our work defined a novel signaling pathway implicated in the control of breast cancer migration.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.262-272
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• 2009

Upstream behavior of glass eels was examined in an experimental eel-ladder at a laboratory of the National Fisheries Research and Development Institute from March to May in 2008. The study was made under various environmental factors and conditions affecting the upstream migration of glass eels in order to design a functional ladder that would allow the passage of glass eels. The experimental eel-ladder consisted of an upper freshwater chamber and a lower sea water chamber; glass eels in sea water can move up to the upper freshwater chamber through the slope (eel-ladder) between them. The optimal condition of the eel-ladder was estimated by comparing the number of glass eels that moved upstream depending on various conditions. Since the glass eels actively moved up the slope to river water rather than to reservoir water or tap water, the experiment was realized using river water. A significantly higher number of glass eels moved up during the spring tide than during the neap tide, and during night than during the day. Upstream movement was significantly higher during high tide than during low tide. Glass eels effectively moved up through a slope of less than $30^{\circ}$ and water-flow velocity lower than 0.4 m/sec. The fish preferred a coarser ladder bed covered with small gravels, brush or carpet.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.3
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• pp.183-193
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• 2022

MicroRNAs (miRNAs) regulate gene expression and are biomarkers for coronary atherosclerosis (AS). A novel miRNA-mRNA regulation network of coronary AS still needs to be disclosed. The aim of this study was to analyze potential mRNAs in coronary AS patients and the role of their upstream miR-491-5p in vascular smooth muscle cells (VSMCs). We first confirmed top ten mRNAs according to the analysis from Gene Expression Omnibus database (GSE132651) and examined the expression levels of them in the plaques and serum from AS patients. Five mRNAs (UBE2G2, SLC16A3, POLR2C, PNO1, and AMDHD2) presented significantly abnormal expression in both plaques and serum from AS patients, compared with that in the control groups. Subsequently, they were predicted to be targeted by 11 miRNAs by bioinformatics analysis. Among all the potential upstream miRNAs, only miR-491-5p was abnormally expressed in the plaques and serum from AS patients. Notably, miR-491-5p overexpression inhibited viability and migration, and significantly increased the expression of contractile markers (α-SMA, calponin, SM22α, and smoothelin) in VSMCs. While silencing miR-491-5p promoted viability and migration, and significantly suppressed the expression of α-SMA, calponin, SM22α, and smoothelin. Overall, miR-491-5p targeted UBE2G2, SLC16A3, and PNO1 and regulated the dysfunctions in VSMCs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.5156-5161
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• 2013

In distributed spatial data stream processing, processed tuples of downstream nodes are replicated to the upstream node in order to increase the utilization of distributed nodes and to recover the whole system for the case of system failure. However, while the data input rate increases and multiple downstream nodes share the operation result of the upstream node, the data which stores to output queues as a backup can be lost since the deletion operation delay may be occurred by the delay of the tuple processing of upstream node. In this paper, the adaptive upstream backup scheme based on operation throughput in distributed spatial data stream system is proposed. This method can cut down the average load rate of nodes by efficient spatial operation migration as it processes spatial temporal data stream, and it can minimize the data loss by fluid change of backup mode. The experiments show the proposed approach can prevent data loss and can decrease, on average, 20% of CPU utilization by node monitoring.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.445-452
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• 2020

In this study, we carried out a distribution and migration boundary lines of chum salmon (Oncorhynchus keta) in the Milyang River. We measured the total length of dead chum salmons. As a results, 40 chum salmons were found during the study period, 25 dead salmons and 15 alive individuals. The ratio of female was 64%. We verified the migration boundary lines of chum salmons based on a sighting survey until detecting a structure that chum salmons are not able to migrate upstream. We discovered that chum salmons were not able to migrate up to 13 km in a mainstream of the Milyang River and up to 12 km in the Danjang stream (a tributary of the Milayang River) from upstream of the Yerim Bridge. Therefore, our results indicate that Milyang River should improve a river connectivity by demolishing weirs that disturb chum salmon's migration or installing appropriate fishways. Also, effective legislations are needed to retain naturality in spawning ground and micro-habitats to increase the survival rate of parrs and smolts.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.245-254
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• 2017

In this study, the flow characteristics and bed changes in the upstream and downstream of weirs with the variation of the weir angels are investigated quantitatively through the laboratory experiments. As the angle of weir increases, the effective weir length decreases. Delta is developed by the sediments inflow upstream and migrates downstream. Delta migration speed decreases as it approaches to the weir upstream, and the size is getting big. As the dimensionless weir length increases, the dimensionless wave length decreases at the downstream of the weir. However, the dimensionless bar height decreases. The dimensionless wavelength increases with the bar height downstream from the weir.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.951-960
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• 2020

This study investigates the adjustment processes of the rivers after weir removal through laboratory experiments. Delta upstream eroded rapidly by flow at the initial stage of the experiments and the knickpoint migrates upward. Moreover, the knickpoint moves fast upward on the condition of alternate bars. The head cutting in the bed is developed fast at the initial stage. However, the erosion speed in the bed decreases with time. The well developed alternate bars migrates with keeping their shape downstream, and the bars affect the channel downstream to adjust new environments after weir removal. Maximum scouring depth downstream and the migration speed decrease over time after removing the weir. The scouring depth in the channel without alternate bars migrates with speed. However, the depth in the channel with alternate bars migrates slow downstream. The channel with alternate bars, in turn, is adjusted well to the new equilibrium states. The maximum scouring depth migrates downstream with time, and the scouring depth and its migration speed decreases with time. The dimensionless maximum scouring depth decreases with the migration speed of dimensionless maximum scouring depth because the deeply scoured places capture the sediments from upstream and the migration speed is slow as the places are filled with them. The dimensionless maximum scouring depth is shallow as the dimensionless backfilling speed is high. The dimensionless maximum scouring depth decreases rapidly less than 5 of dimensionless backfilling speed. However, the depth decreases slow more than 5 of it.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.6
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• pp.754-770
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• 1994

Suspended sediment distribution and water column processes in the upper Neuse River estuary, North Carolina, were monitored monthly from February 1988 through February 1989, in order to identify the turbidity maximum, to determine its temporal and spatial variation under changing conditions(freshwater runoff, wind, and tide). During most of the observation periods a weak turbidity maximum, associated with the estuarine circulation processes, developed at a flow convergence zone, near the upstream limit of salt intrusion. No turbidity maximum was found when the water column was vertically homogeneous with respect to salinity and when there was no consistent upstream bottom flow. Annual migration of the turbidity maximum, accompanied by migration of salt intrusion, was over 20 km of the upper estuary. Due to the coincidence of dominant wind direction(NE-SW) with the main orientation of the Pamlico-Neuse system, wind played the dominant role in dynamics of the turbidity maximum by influencing the degree of salinity stratification and the extent and strength of estuarine circulation. Tidal effects on the sediment dynamics were negligible.

• Journal of Korea Water Resources Association
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• v.56 no.spc1
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• pp.1037-1048
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• 2023

Fishways are constructed to ensure the fish migration because river-crossing structures such as dams and weirs cut off the stream longitudinal connectivity and influence on aquatic ecosystems. However, the passage efficiency of fishes varies depending on flow characteristics in the fishway and fish species. In this study, three-dimensional numerical simulations are carried out using a RANS model and the volume of fluid method for resolving free surface fluctuations to calculate the turbulent flow in the pool and weir type fishway. The Flow velocity and turbulent kinetic energy in the pool of fishway are analyzed according to variation of the upstream water level and the length of pool. The present numerical simulations reasonably well reproduce the stream flow and plunging flow characteristics in the pool. The simulation results show that the stream flow changes to the plunging flow as the length of the pool increases. When the upstream level increases, the stream flow becomes more evident. Key parameters related to the fish migration within the fishway such as the flow velocity and the turbulent kinetic energy are examined to assess the ascending possibility of fishes.